/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

#ifndef THRIFT_TMULTIPLEXEDPROTOCOL_H_
#define THRIFT_TMULTIPLEXEDPROTOCOL_H_ 1

#include <thrift/protocol/TProtocolDecorator.h>

namespace apache 
{ 
    namespace thrift 
    { 
        namespace protocol 
        {
            using boost::shared_ptr;

            /**
             * <code>TMultiplexedProtocol</code> is a protocol-independent concrete decorator
             * that allows a Thrift client to communicate with a multiplexing Thrift server,
             * by prepending the service name to the function name during function calls.
             *
             * \note THIS IS NOT USED BY SERVERS.  On the server, use 
             * {@link apache::thrift::TMultiplexedProcessor TMultiplexedProcessor} to handle requests
             * from a multiplexing client.
             *
             * This example uses a single socket transport to invoke two services:
             *
             * <blockquote><code>
             *     shared_ptr<TSocket> transport(new TSocket("localhost", 9090));
             *     transport->open();
             *
             *     shared_ptr<TBinaryProtocol> protocol(new TBinaryProtocol(transport));
             *
             *     shared_ptr<TMultiplexedProtocol> mp1(new TMultiplexedProtocol(protocol, "Calculator"));
             *     shared_ptr<CalculatorClient> service1(new CalculatorClient(mp1));
             *
             *     shared_ptr<TMultiplexedProtocol> mp2(new TMultiplexedProtocol(protocol, "WeatherReport"));
             *     shared_ptr<WeatherReportClient> service2(new WeatherReportClient(mp2));
             *
             *     service1->add(2,2);
             *     int temp = service2->getTemperature();
             * </code></blockquote>
             *
             * @see apache::thrift::protocol::TProtocolDecorator
             */
             class TMultiplexedProtocol : public TProtocolDecorator
            {
            public:
                /**
                 * Wrap the specified protocol, allowing it to be used to communicate with a
                 * multiplexing server.  The <code>serviceName</code> is required as it is
                 * prepended to the message header so that the multiplexing server can broker
                 * the function call to the proper service.
                 *
                 * \param _protocol    Your communication protocol of choice, e.g. <code>TBinaryProtocol</code>.
                 * \param _serviceName The service name of the service communicating via this protocol.
                 */
                 TMultiplexedProtocol( shared_ptr<TProtocol> _protocol, const std::string& _serviceName ) 
                    : TProtocolDecorator(_protocol),
                      serviceName(_serviceName),
                      separator(":")
                { }
                virtual ~TMultiplexedProtocol() {}

                /**
                 * Prepends the service name to the function name, separated by TMultiplexedProtocol::SEPARATOR.
                 *
                 * \param [in] _name   The name of the method to be called in the service.
                 * \param [in] _type   The type of message
                 * \param [in] _name   The sequential id of the message
                 *
                 * \throws TException  Passed through from wrapped <code>TProtocol</code> instance.
                 */
                uint32_t writeMessageBegin_virt(
                    const std::string& _name, 
                    const TMessageType _type, 
                    const int32_t _seqid);
            private:
                const std::string serviceName;
                const std::string separator;
            };

        }
    }
}

#endif // THRIFT_TMULTIPLEXEDPROTOCOL_H_
